The present invention disclosed herein relates to a multi-layer interconnection structure and a manufacturing method thereof, and more particularly, to a multi-layer interconnection structure including a via contact that electrically connects a plurality of wirings on the top and bottom of an interlayer insulation layer, and a manufacturing method thereof.
In general, a variety of semiconductor devices on a substrate require a multi-layer interconnection structure. A typical multi-layer interconnection structure includes a contact plug formed of a conductive metal material that penetrates through an interlayer insulation layer in order to electrically connect a plurality of wirings on the top and bottom of the interlayer insulation layer of a semiconductor device.
However, a contact plug essentially requires a photolithography process and an etch process during which a contact hole is formed to expose a bottom wiring by patterning an interlayer insulation layer on a bottom wiring. Additionally, the contact plug additionally requires a chemical mechanical polishing (CMP) process during which a conductive metal layer filled in the contact hole is removed evenly from the interlayer insulation layer.